1. Field of the Invention
This invention relates to enhanced network services using a subnetwork of communicating processors.
2. Description of Related Art
A computer network having more than one possible message delivery path, such as for example a network of computer networks (an xe2x80x9cinternetworkxe2x80x9d), generally comprises a set of processors which have the task of routing each message from its source to its destination. These processors (herein called xe2x80x9croutersxe2x80x9d, but sometimes called xe2x80x9cbridgesxe2x80x9d, xe2x80x9cbroutersxe2x80x9d, or other terms) generally interoperate using a common distributed routing technique. For example, (1) routers generally exchange information about routing conditions in the network, so as to globally inform all routers of conditions which are detected locally, (2) routers generally each route messages according to the same techniques using the same routing technique.
The collection of routers (herein called the xe2x80x9csubnetxe2x80x9d of routers) thus has access to a rich collection of distributed information about the status of the network needed for routing messages therein, including detailed and up-to-date information about the network topology, relative distance measures in the network, administrative policies in force in the network (such as, for example, network xe2x80x9cfirewallsxe2x80x9d or routers which will route only a subset of messages), and other information. It would be advantageous to provide at least some of this distributed information to applications which might use it to provide enhanced services. Examples of such enhanced services, and how they would be provided, are described herein.
The router subnet also provides a powerful and available resource for distributing other information, not strictly required for the task of routing messages in the network, such as, for example, relative load at each host in the network. It would be advantageous to disseminate this information and provide at least some of it to applications which might use it to provide enhanced services. Examples of such enhanced services, and how they would be provided, are described herein.
Accordingly, it would be advantageous to provide a method and system for enhanced network services using a subnetwork of communicating processors.
The following U.S. Patent(s) or other documents may be pertinent:
R. Srinivasan, xe2x80x9cRPC: Remote Procedure Call Protocol Specification Version 2xe2x80x9d, Network Working Group RFC 1831 (August 1995).
The pertinence of the related art will also be apparent to those skilled in the art after perusal of this application.
The invention provides a method and system for providing enhanced services for a network, using a subnetwork of communicating processors. The enhanced services use information about the network which is available to the subnet of communicating processors (such as a set of routers), interoperating using a common distributed technique for disseminating that network information. In a first aspect of the invention, the router subnet collects network topology information and provides a service using that network topology information, responsive to requests from non-routers (such as host processors) coupled to the network. The network topology information comprises information about paths and routes, including bandwidth, connectivity, delay, traffic reservations, and administrative policies applicable to those paths and routes. Routers providing the enhanced service have the option of requiring authentication for service requests.
For a first example, the router subnet provides an enhanced distributed naming service which, in addition to translating server names into host addresses, also orders those host addresses by relative distance in the network, or by another criterion designated by the client. For a second example, the router subnet provides an enhanced message delivery service which, in addition to delivering a message to a plurality of destinations, assures that all destinations receive the message at substantially the same time.
In a second aspect of the invention, the router subnet collects information advertised by hosts coupled to the network, and disseminates that host information to substantially all routers, using the common distributed technique for disseminating network topology information. In a first preferred embodiment, the host information comprises information about server processes available at the originating host (such as what services are available and to which users those services are available). In a second preferred embodiment, the host information comprises information about client processes operating at the originating host (such as which users are operating those client processes and which services they desire).
For a first example, hosts advertise their relative load for dissemination by the router subnet, and the router subnet provides an enhanced distributed naming service which, in addition to translating server names into host addresses, also orders those host addresses by relative load (or by both relative distance and relative load). Similarly, hosts may also advertise other server information, such as cost for performing the service, delay in performing the service, or other administrative policies which would affect the choice of server.
For a second example, hosts advertise their logged-in users for dissemination by the router subnet, and the router subnet provides an enhanced message-delivery service which, in addition to receiving messages for delivery, also delivers those messages to the host where the destination user is logged-in. Similarly, hosts may also advertise other client information, such as willingness to pay for performing a designated service, which the router subnet may disseminate for responses by servers or by other clients.